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Abstract This technical brief reports an experimental investigation on the effect of feed region density on resultant sintered density and intermediate densities (powder bed density and green density) during the binder jetting additive manufacturing process. The feed region density was increased through compaction. The powder bed density and green density were determined by measuring the mass and dimension. The sintered density was measured with the Archimedes’ method. As the relative feed region density increased from 44% to 65%, the powder bed density increased by 5.7%, green density by 8.5%, and finally sintered density by 4.5%. Statistical testing showed that these effects were significant. This study showed that compacting the powder in the feed region is an effective method to alter the density of parts made via binder jetting additive manufacturing.
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Metal Binder Jetting Additive Manufacturing: A Literature Review
Abstract Binder jetting is an additive manufacturing process utilizing a liquid-based binding agent to selectively join the material in a powder bed. It is capable of manufacturing complex-shaped parts from a variety of materials including metals, ceramics, and polymers. This paper provides a comprehensive review on currently available reports on metal binder jetting from both academia and industry. Critical factors and their effects in metal binder jetting are reviewed and divided into two categories, namely material-related factors and process-related parameters. The reported data on density, dimensional and geometric accuracy, and mechanical properties achieved by metal binder jetting are summarized. With parameter optimization and a suitable sintering process, ten materials have been proven to achieve a relative density of higher than 90%. Indepth discussion is provided regarding densification as a function of various attributes of powder packing, printing, and post-processing. A few grades of stainless steel obtained equivalent or superior mechanical properties compared to cold working. Although binder jetting has gained its popularity in the past several years, it has not been sufficiently studied compared with other metal additive manufacturing (AM) processes such as powder bed fusion and directed energy deposition. Some aspects that need further research include the understanding of powder spreading process, binder-powder interaction, and part shrinkage.
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- Award ID(s):
- 1762341
- PAR ID:
- 10165724
- Date Published:
- Journal Name:
- Journal of Manufacturing Science and Engineering
- Volume:
- 142
- Issue:
- 9
- ISSN:
- 1087-1357
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1115/1.4047430
